This application describes an overtube/introducer device that gives access to body cavities using natural orifices of the body (e.g., esophagus, anus, vagina) for a variety of therapeutic and/or diagnostic procedures. In a particular application, the overtube/introducer enables the introduction of devices into the gastrointestinal tract of a patient via the mouth and esophagus. Therapies to be carried out using the introducer can include procedures designed for the treatment of obesity. The disclosed overtube provides in and out access to the targeted procedural site and protects the body tissue during the procedure from trauma.
The disclosed overtube is suitable for use in an exemplary procedure in which the geometry of the stomach is modified and implantable devices are deployed. The procedure is preferably performed entirely through the naturally existing orifice of the mouth, without additional external incisions.
The exemplary procedure is initiated with the introduction of an overtube into the mouth and, at a minimum, past the pharynx of a patient but preferably reaching and sealing against the lower esophageal sphincter (LES). For reference, FIG. 1 shows the anatomy of the human head and stomach, with reference numerals identifying the following features:
1. Body of stomach
2. Fundus
3. Anterior wall
4. Greater curvature
5. Lesser curvature
6. Lower esophageal sphincter (LES) I gastroesophageal junction
9. Pyloric sphincter
10. Pyloric antrum
11. Pyloric canal
12. Angular notch
13. Gastric Canal
14. Rugal folds
The entire exemplary procedure is preferably performed under direct endoscopic visualization, obtained by inserting a flexible endoscope into the overtube prior to its introduction into the patient, though the procedure (or individual steps of the procedure) may also be performed without direct visualization. In cases where an endoscope is used, the endoscope's distal tip may be inserted into a flexible Bougie that incorporates a central lumen allowing direct line-of-sight for the endoscope's illumination and visualization optics. The endoscope with the installed Bougie may then be inserted into the overtube's central lumen until the Bougie protrudes just past the overtube's distal end. This provides a gentle leading edge that facilitates insertion of the Bougie, overtube, and endoscope into the patient's esophagus.
Alternatively the overtube may be inserted over a guide wire; the guidewire inserted under direct visualization using a standard endoscope. A transition member is positioned between the inside diameter of the overtube and the outside diameter of the guidewire providing for a smooth transition. This transition is preferably a long taper, and composed of a soft, flexible material such as silicone.
Once the overtube, endoscope and Bougie have reached the desired position within the esophagus, the endoscope and Bougie are withdrawn from the overtube, and the overtube is left in position. The overtube is now in a position to facilitate the introduction of other tools and devices needed to perform subsequent steps.
With the overtube in the desired position, a special-purpose stapler is inserted which will be used to prepare sites within the stomach wall tissue that will serve as mounting points for implantable devices to be installed in later steps. Staplers suitable for this procedure include those disclosed in the following U.S. applications: U.S. application Ser. No. 11/542,457, filed Oct. 3, 2006, U.S. application Ser. No. 11/900,757, filed Sep. 13, 2007, U.S. application Ser. No. 12/119,329, filed May 12, 2008, U.S. application Ser. No. 12/050,169, filed Mar. 18, 2008.
In one such stapler, the leading distal tip of the stapler mechanism is covered with a compliant, bullet-shaped, Bougie end cap, and incorporates a side-looking window. The smooth Bougie shape of the end cap facilitates introduction of the stapler into the overtube and past the distal end of the overtube into the patient's esophagus or stomach. The side window allows stomach wall tissue to be drawn between the stapler jaws prior to the application of staples. The stapler incorporates a passive flexible length which allows the device to bend freely between the user controls at the proximal end and the stapler mechanism at the distal end. Insertion of the stapler is preferably performed under direct endoscopic visualization, with an endoscope positioned next to the stapler such that its camera optics are located slightly proximal of the stapler's distal end. In this way, the position of the stapler may be visualized at all times, relative to its position within the overtube, esophagus and stomach. However, insertion of the stapler may optionally be performed without using an endoscope for visualization.
With the stapler inserted into the stomach, it may then be positioned relative to the stomach wall near the lower esophageal sphincter as desired. In order to achieve the desired position and visualization, it may be necessary to withdraw or further insert the overtube, or to manipulate certain features of the overtube, in such a way that it advantageously alters the geometry of the tissue and/or the overtube's relative position. When the position of the stapler is judged to be correct, suction is applied to draw stomach wall tissue into the stapler end cap's side-looking window. This positions the stomach wall tissue between the jaws of the stapler, which are then approximated via a physician-controlled actuator to clamp the tissue firmly in position. Once the tissue has been securely fixtured, the suction may be released, as it is no longer needed to retain the stomach tissue. Staples are then deployed by means of a second physician-controlled actuator through the plication, or fold, of stomach tissue between the stapler's jaws to create circular rings about a central point. A hole is created in the plication of stomach tissue at the center of the pattern of stapes simultaneous to the application of the staples. The hole and surrounding circular array of staples create a secure and durable mounting point (e.g., for implantable devices), and will be used in later steps of the procedure. Once the staples have been deployed and the mounting point has been created, the physician releases the plication from the stapler's jaws and any remaining suction. The stapler and endoscope are then withdrawn from the overtube.
For staplers that must be re-loaded prior to the creation of the next mounting point, the stapler is withdrawn from the overtube and the distal stapling mechanism is then reloaded. For self-reloading stapler mechanisms, this step is not required. If reloading is required and has been performed, the reloaded device, Bougie end cap and endoscope are reinserted into the overtube. The process of positioning the stapler mechanism within the stomach described above is repeated so that the next mounting point is identified and created. This process is repeated to produce one or more anchor points, but preferably four mounting points are created. These mounting points may be anywhere within the stomach, but they are preferably located at the 3, 6, 9 and 12 o'clock positions, a fixed distance away from the lower esophageal sphincter. If the mounting points are to be used as anchor points for a flow restrictor of the type used to restrict/obstruct passage of food from the esophagus into the stomach, the preferential distance of the mounting points is such that the position of the exit of a restrictor attached at the mounting points will be immediately adjacent the lower esophageal sphincter. Exemplary restrictor devices include but are not limited to those disclosed in U.S. Pat. Nos. 6,675,809, 6,845,776, 7,097,665, and 7,146,984, U.S. application Ser. No. 10/345,666, filed Jan. 16, 2003, and U.S. application Ser. No. 12/175,242 (abandoned), Endoscopic Implant System and Method, filed Jul. 17, 2008.
Once the desired mounting points have been created with the stapler, the stapler is withdrawn. Next, highly compliant anchors are installed through the hole at the center of each of the mounting points. The anchors have a rivet-like shape with large retaining heads on either end. The anchors are intended to be installed in the holes at the center of the mounting points, remain in position indefinitely or until removed, and be easily removable. The anchors are configured such that they may be grasped and pullet! from one end (herein referred to as the “leading end”), and the resulting tension causes the leading end retaining head to change profile so that it may be drawn through the hole in a mounting point. The other end of the anchor (herein referred to as the “following end”) is designed so that tension resulting from drawing it through the mounting hole does not result in a change to its profile, so it cannot be drawn through the mounting hole. Anchors of this type are described in U.S. application Ser. No. 12/175,242 (abandoned), Endoscopic Implant System and Method, filed Jul. 17, 2008.
Anchors are positioned in each of the mounting holes by means of graspers or similar instruments, which pull them, leading end first, through the mounting holes. Once the anchors are installed, the instruments required to insert them are withdrawn from the overtube.
Finally, a restrictor is inserted into the stomach via the overtube. The restrictor is attached to the anchors, and will remain in the stomach after the procedure for an indefinite period of time, such as the point in time when a physician determines the patient has achieved sufficient weight loss. The restrictor is attached to the anchors by drawing the leading end of the anchors through mounting holes in the restrictor using graspers or other instruments, as appropriate.
When the restrictor is attached to the anchors, the procedure is complete and the overtube may be withdrawn from the patient, along with any tools remaining in the lumen it defines (e.g., endoscope, graspers, etc.).
Upon completion of the procedure, the overtube has enabled the deployment of a restrictor, which is attached to anchors that have been implanted into stapled plications in the stomach wall. The passage of food into the stomach from the esophagus has been restricted, altering the patient's feelings of satiety and eating habits.